At 23.31 hours on 20 Sep 1941, U-124 fired three torpedoes in two minute intervals at convoy OG-74 north-northeast of the Azores and heard one detonation, then a tanker was observed being hit (there was a burst cloud). Another ship was hit and sank immediately after a heavy explosion. Mohr claimed two ships with 15.000 grt sunk and another with 8000 grt damaged. In fact, the Baltallinn and the Empire Moat were hit and sunk.

The master, 28 crew members and three gunners from the Empire Moat (Master James Fawcett Travis) were picked up by the British rescue ship Walmer Castle (Master Gerald Lewis Clarke).On 21 September, five crew members were lost when the rescue ship was bombed and sunk northeast of the Azores in 47°16N/22°25W by a German Fw 200 aircraft of I./KG 40. The remaining men from the Empire Moat were picked up by the HMS Marigold (K 87) (Lt W.S. Macdonald) and the HMS Deptford (L 53) (LtCdr H.R. White) and landed at Gibraltar on 28 September.